Preparation of Titania/PDMS Hybrid Films and the Conversion to Porous Materials

摘要

Transparent films of titania/poly(dimethylsiloxane) (PDMS) hybrids were prepared by the solvent evaporation from the precursor solution prepared by the co-hydrolysis and co-condensation of titanium tetraisopropoxide and a methoxy-functionalized PDMS.The hybrid films were flexible and had high homogeneity of the composition.The organic groups of PDMS were decomposed at 400 deg C in air to form porous films.Though the heated films were rather brittle compared to the as-synthesized films,they were still transparent and homogeneous.The BET surface areas of the films after the heat treatment at 400 deg C were over 300 m~2/g,while the as-synthesized hybrid films were non porous.According to the BDDT classification,the nitrogen adsorption/desorption isotherms of the calcined films were Type I,showing that the films were microporous.The titania domains were still amorphous after the heat treatment at 400 deg C and transformed to anatase after the heat treatment at 1,000 deg C.